Lamp focusing



Feb; 7, 1928.

H. C. FOSTER LAMP FOCUS ING Filed Jan. 29, 1925 2 Sheets- Sheet I 1 541%,, ymu P am A14, ATTORNEY-5 H. C. FOSTER LAMP FOCUS ING Filed Jan. 29,1925 2 Sheets-Sheet 2 Fig. /0. @313 flbt ovmmf ar/guru",

Patented Feb. 1, 1928.

UNITED STATES 1,658,556 PATENT OFFICE.

HARRY O. FOSTER, OF GONNERSVILLE, INDIANA, ASSIGNOR, BY DIRECT AND MESNE ASSIGNMENTS, F ONE-HALF TO INDIANA LAM]? CORPORATION, OF CONNERS- VILLE, INDIANA, A CORPORATION OF DELAWARE, AND ONE-HALF TO GENERAL MOTORS CORPORATION, OF DETROIT, MICHIGAN, A CORPORATION OF DELAWARE.

name rocusme.

Application filed January This invention relates to lamp focusing and is herein illustrated as embodied 1n focusing devices for the lamps of automobile headlight reflectors.

In automobile headlights, in use at the present day, one 015 the main sources of glare is due to the fact that the lamps are out of focus.

One of the objects of this invention, there- 1 fore, is to provide an easily accessible focusing device capable of accurately ad ust ng a filament into focus and maintainlng 1t 1n adjustment.

an improved focusing device for adjusting a lamp longitudinally of the reflector axis or transversely thereof in any desired direction and to a fine degree. Another object 1s to provide a reliable focusing device of very simple, compact, and inexpensive construcac tion.

To these ends and also to improve generally upon devices of the character indicated my invention consists in the various matters hereinafter described and claimed.

lln the drawings, Figure 1 is a central vertical section.

Figure 2 is a front elevation with the reector partly broken away.

Figure 3 is a rear elevation with the recu flector partly broken away.

Figures 4, 5, 6 and 7 are vertical sections of other forms of the invention.

Figure 8 is a transverse section onthe line 8-8 of Figure '2' Figures 9 and 10 are central vertical sections of other forms of the invention and Figure ll is a transverse vsection on the line 11'1l of Figure 10.

The numeral 10 designates a parabolic reflector which, in each instance, has a central opening through which a lamp socket or sleeve 11 is longitudinally movable. This reflector is mounted in the usual casing, a portion of which is indicated at 8. Held in the socket, is the usual lamp bulb 12 having a centrally arranged filament 13; The bulb 12 is removably secured in the socket by the usual pin it and bayonet slot 15. Tu Figure l, a perforated plate 16, having a peripheral flange 17, closely surrounds the socket 1-1. The inner edge of the plate is curled about the rim of the opening in the reflector to form a support onwhich the Another object is to provide 29, 1925-- Serial No. 5,529..

socket 11 can slide and tilt. The flange 17 bears against a packing ring 18 to cushion its engagement with the reflector. A second flanged and perforated plate 19, which may be stamped out by the same die as the plate 16, is fixed in any suitable way to the socket 11.

Passing loosely through aligned openings in the two plates 16 and 19 arejaseries of bolts 20, herein shown as three, which have their heads 22 accessible through openings 24 in the reflector at the sides of the lamp. The heads of the bolts are maintained in contact with the inner face of the plate 16 by coil springs 21 interposed between the plates. Each bolt hole in the disc 19 is larger than its bolt and a nut 23 is threaded on each bolt and held against turning by the outer flange of the plate 19. By turning all the bolts to the same degree, the socket 11 will be longitudinally shifted through the opening in the reflector. By turning the bolts in varying degrees, the plate 19 can be tilted and, by reason of its rigid connection with the socket 11, the latter will be likewise tilted about the rim of the opening in the reflector which acts as a fulcrum. This action naturally forces the plate 19 to one side or another of its axis, this movement being permitted by the openings in the plate, Hence, the lamp filament has universal adjustment laterally or transversely to place it exactly in the axis of the reflector and it also has longitudinal adjustment to place it at the focus. Lighting current is supplied through the usual flexible conductor 32 extending from the rear of the socket 11.

In Figure 4, the reflector 10 has outwardly pressed portions 116 to form seats for the olt heads 22 and the rim of the central opening is curled to form a fulcrum on which the socket 11 can tilt.

In Figure 5, the lamp is adjustable from the rear of the lamp casing 33, through holes 34, rather than from the front of the reflector, although, if desired, both ends of the bolts may be slotted and aligned openings formed in the reflector will enable adjustment to be made from either end. In this figure, a flanged plate 216 holds the nuts 23 from turning and the plate has a sleeve portion with "its edge bent around the edge of the reflector. A felt sleeve 29 makes the ltd Mill

opening dust proof and will y eld when the socket tilts. o prevent access of dust from the rear of the casin the openings 34 may be closed by a turnab e disc 35 having openings 36 which can be made to register with the o nings 34.

In igure 6, the bolts 20 are not connected with the reflector, except through the lamp casing, but are pa$ed loosely through the lamp casin 33 and have their heads 22 outside. In t is case a plate 119 with flanges extending forwardly holds the nuts from turning and the springs 21 are inserted be tween the plate and the casing 33.

In Figure 7, the reflector 10 has a bead 37 at the rim of its central opening but this opening is larger than the socket 11 to allow clearance. A washer or sleeve-like piece of flexible material 38 may be attached to the head to close the s ace. The socket 11, in this form, is exten ed through the back of the casing 33 to receive the usual plug from which currentis supplied to the lamp. The opening in the casing is also lar er than the socket and a flan ed washer 39 c osely fittin the socket 11 c oses the openin A co1 spring 221, inter osed between t e washer 39 and a flan e plate 119 fixed to the socket, holds t e washer against the inner face of the casing and holds the bolt heads 22 against the outer face of the casin The tilting of the socket in this form Wlll take place about an axis near the plane of the plate 119 and the ends of the socket move in opgosite directions.

In igure 9, there is a clearance between the socket 11 and the reflector and between the socket and the lamp casing 33 and a felt ad 138 closes the openin in the reflector.

he casing 33 has a prcsse out central portion with a rolled flange 4O for.holding the lar er end of a'volute spring 321, the smaller cm? of the spring abutting the rear face of the flanged plate 119.

Figure 10 is similar to Figure 6 but the space between the reflector 10 and the cas1ng 33 is so great that a second socket 41 1s placed in line with the socket 11 to receive the usual plug. The socket 41 is carried by.

a flanged plate 42 held in an opening in the Lucas casing 33' by bolts 20. A slack flexible coni ductor 43 allows the socket 11 to tilt without impairing the electrical connection. The p1ate'219 has its inner and outer flanges extending in opposite directions from the body of the plate and this plate and the plate 42 may be stamped up1 by the same die.

11 each form of t e in and the casin provide a compartment for the focusing evice which is accessible for operation from the outside.

Although the invention has been illustrated 'by reference to certain illustrated forms, it should be understood that, in its broader aspects, the invention is not necessarily limited to the specific construction selected for illustrative purposes.

I claim:

1. In'a device of the character described, a reflector having a central 0 ning, a lamp socket slidable longitudina y through the opening and adapted to tilt on the rim of the opening, a lamp in the socket and a plurality .of independently o erable bolts connected to the socket and to tie reflector for sliding or tilting the socket.

2. In a device of the character described, a reflector havin a central opening, a lamp socket slidable llmgitudinally through the opening and adapted to tilt on the rim of the opening, alamp in the socket, a plate fixed to and surrounding the socket, a pluralit of independentl o rable bolts connectmg the plate and t e reflector, and springs surrounding the bolts and interposed between the plate and the reflector.

L 3. In a device of the character described, a reflector having a central opening, a lamp socket slidable lon 'tudi'nally through the opening and adapt to tilt on the rim of the opening, a lamp 1n the socket, a flanged plate fixed to and surrounding the socket, a pluvention, the reflector I rality of inde endently operable bolts connecting the p ate and the reflector, springs interposed between the plate and the reflector, and nuts held from turnin by the flanged plate and threaded on said Its.

In testimony whereof I aflix my signature.

HARRY. o. FOSTER. 

